1. Field of the Invention:
This invention relates to a surgical needle for suturing tissues in cosmetic surgery, plastic surgery and so on, and more particularly is directed to improvements in the curved surgical suturing needle having curvature decreasing gradually from the rear end toward the needle point, which improvements consist in effectively smoothing suturing operation of tissue in plastic surgery or the like.
2. Description of the Prior Art:
For suturing tissue in cosmetic surgery, plastic surgery and so on, a surgical suturing needle which is curved uniformly over the entire length in a substantially semicircular or quadrant shape has generally been used. The inventor of this invention formerly proposed a surgical needle which is curved somewhat sharply in part (Japanese Patent Appln. Pub. Disclosure SHO 63-38441(A)). Also, the inventor proposed a curved surgical needle composed of a leading half portion having a relatively smaller curvature and a rear half portion having a larger curvature (Japanese Utility Model Appln. Public Disclosure SHO 64-54515(A)).
A surgical needle is generally provided in its crown portion (rear end) with a thread hole or notch for allowing a suture thread to pass therethrough or be hooked. Surgical suture of tissue is carried out in such a manner that the suturing needle held at its rear end portion by a needle holder is stuck into the tissue and passed around an incision in the tissue so as to form a spiral suture continuously along the incision. The use of the curved needle shaped in a circular arc makes it possible to effectively suture the tissue in theory.
However, when the surgical needle having a steeply curved leading portion is practically used to suture, it is difficult to stick the needle into the tissue perpendicularly to the skin on account of softness and elasticity of the tissue. When using a surgical needle with a leading portion having a small curvature, the step of pulling out the needle stuck through the tissue becomes much harder. Thus, it would appear that the surgical needle comprising the leading half portion having small curvature and the rear half portion having large curvature as proposed by the aforenoted Japanese Utility Model Application Public Disclosure SHO 64-54515(A) is the most acceptable for surgically suturing purpose.
The surgical needle is generally provided in its crown portion (rear end portion) with a thread hole. The thread hole provided is typically formed by longitudinally cutting the crown portion into opposite pieces and bringing the opposite pieces into springy contact with each other. Though a suture thread can readily be inserted with a single operation into the thread hole thus formed, it entails a structural drawback in that the suture thread inserted in the thread hole easily comes out from the thread hole in surgical operation. Besides, since the suture thread inserted in the thread hole is folded backward at the thread hole, the thread is protrudes laterally from either side surface of the needle. The laterally protruding portions of the thread would injure excessively the tissue and thin blood vessels in needling, thereby to involving profuse bleeding, subcutaneous hematoma or the like. As a result, convalescence will be lengthened.